1. Field of the Invention
The present invention relates to a structure for connecting a crimping terminal and an electric wire.
2. Description of the Related Art
A reduction in weight of a vehicle exerts significant influence on fuel efficiency. At the present time, when carbon dioxide emission is required to be reduced, particularly, in electric vehicles or hybrid vehicles in which a wire harness is used more than gasoline vehicles, it is convenient that an electric wire made of aluminum or aluminum alloy of lightweight material is used for the wire harness. However, if water is interposed to contact sections of both of the electric wire and a terminal in a state in which the electric wire made of aluminum, which is formed of aluminum or aluminum alloy, is crimped and connected to the terminal made of copper, which is formed of copper or copper alloy, the water becomes an electrolytic solution between dissimilar metals. If the dissimilar metals such as a copper terminal and an aluminum conductor become electric circuits through an electrolytic solution, because of a difference between corrosion potentials of both of them, corrosion of a metal of a lower potential (for example, aluminum conductor) is prompted. That is, galvanic corrosion is generated.
Here, a crimping terminal is proposed, which is capable of preventing electrolytic corrosion while securing conductivity, even when an electric wire conductor to be crimped by barrel pieces is made of a dissimilar metal (refer to below described PTL 1).
A female crimping terminal (crimping terminal) 501 illustrated in FIG. 6 includes barrel pieces 507 constituting a crimping section 505 which surrounds and crimps an exposed part of an aluminum core wire 503 in both sides of a width direction. The barrel pieces 507 are made of a dissimilar metal (for example, copper) which has different conductivity from that of the aluminum core wire 503. An insulation coating section 511 (water stop sheet, or the like) is included in a surrounding surface 509 of the crimping section 505. The insulation coating section 511 is formed longer than a length of the exposed part of the aluminum core wire 503. The female crimping terminal 501 is crimped by the barrel pieces 507, so that the crimping section 505 surrounds integrally from a tip side further than a tip of the aluminum core wire 503 to a sheath part of a tip side of a sheathed electric wire 513. Accordingly, the insulation coating section 511 or the water stop sheet which is a waterproof material is interposed and seals between the aluminum core wire 503 and the crimping section 505, and therefore, infiltration of water is prevented and galvanic corrosion is prevented from being generated.
PTL 1 is JP-A-2012-69449 (see FIG. 7,Paragraph 0113).